A couple of weeks ago I shared an assortment of facts about chickens. Today I’m going to share a few things only a chicken person would know.
A hen’s egg-laying apparatus–it’s officially called the oviduct–is like an assembly line. Before I had hens, I knew nothing about this sort of thing, so I’m happy to share what I’ve learned. It’s FASCINATING.
Like a woman, a hen is born with all the eggs she will ever lay–or at least the yolks, that is. (Not full-sized yolks, you understand. Tiny little yolks.) Every 22 hours or so, depending on the chicken breed, a mature yolk leaves the ovary and travels down the oviduct on its way to the “vent.” (Everything that comes out of a hen’s rear comes through the vent. But different tubes lead to the vent, so there’s no co-mingling.)
At the first assembly station, the white is wrapped around the yolk. At the next station, the shell encases the yolk and white. At the next station, the shell is “spray painted” with whatever colors are common to that hen’s breed. (My girls lay white, tan, blue, and chocolate brown eggs). At the very last station, a thin, clear membrane is applied to the shell, so that when it is laid in the sand or straw, the tiny pores will be sealed against dirt and bacteria.
You do not have to refrigerate freshly-laid eggs UNLESS YOU WASH THEM. If you wash them, you’re washing away the protective coating, so they need to go into the fridge. They will keep about a month sitting out on the counter. In Europe, they sell unfrigerated eggs. In the U.S., the egg you buy in the grocery store may be spotless, but it may also be three months old. As an egg ages, air seeps into the egg through the pores. You can determine which egg is old and which is fresh by putting them into a pan of water. Old eggs float because they’re full of air. Fresh eggs sink.
If the hen has been with a rooster, the yolk will have been fertilized, but the chick will not begin to develop until the day near-constant heat is applied–99.5 degrees. So a hen could lay six or seven or ten eggs over a couple of weeks, and they will hatch together, approximately 21 days after she begins to sit on them. (I tell you, God outdid Himself with the chicken.)
Now . . . occasionally mishaps occur. I once cracked a freshly-laid egg into my frying pan and gasped when the yolk was brown and stunk to high heaven. Apparently that yolk had stalled along the oviduct and rotted inside the hen’s body before it went through the shelling and shrink-wrapping stages. Fortunately, that rarely happens.
Sometimes a hen will lay a “fairy egg.” These are about the size of a Jordan almond. There is no yolk inside. Apparently a yolk forgot to leave the ovary, so the white didn’t have much to surround, and the shell didn’t have much white . . . you get the picture.
Sometimes two yolks will leave the ovary at the same time, and you’ll get a slightly-larger, double-yolked egg. Some hens have a tendency to lay double-yolked eggs, and that’s fine. I know what you’re thinking–could a fertilized double-yolked egg successfuly hatch? Not likely, though it does occasionally happen. But since the chicks breathe the air in the shell until they hatch, it’s not likely that two chicks would have enough air to survive until hatch time.
The other day I found a fairy egg in the nest box. (They always make me smile.) And a few days later I found a ginormous egg in the chicken run–if it had been round, it’d have been a softball. All I can figure is that the hen’s missing yolks got together in the pipeline and created a monster. I haven’t cracked that egg yet, but I’m guessing there are two or three yolks inside.
Those little brown spots you occasionally see in the egg? Harmless. The little globs of white stuff that you sometimes see on the yolk? Those are the chalazae, two little muscles that attach the yolk to the shell and hold it in place. (You wouldn’t want your egg scrambled before you cracked it, right?)
Why are my egg yolks a beautiful orange yellow while grocery store eggs are paler? Because my chickens are allowed to step out on occasion (when the dogs are in the house) to eat grass. The color comes from Xanthophylls. The more plants and grass a chicken eats, the more yellow their egg yolks will be.
Can you eat fertilized eggs? Of course. The eggs will not develop AT ALL until the hen begins her official “sitting” or “brooding.” Before she applies that constant heat, the egg is on hold, and you, the eater, wouldn’t be able to tell a fertile egg from an unfertilized one.
Smaller chickens (bantams) lay smaller eggs. Bigger chickens lay bigger eggs. And no, the humongous egg below isn’t from an ostrich or duck–it came from one of my hens, probably the girl who laid the fairy egg.
I think she deserves a week off. 🙂
About that ginormous egg–I cracked it and found a normal egg inside! If you’re interested in an entertaining and educational video about how such things occur, check it out here.
I hope you’ve enjoyed this little tutorial on eggs. The next time you hold one, marvel at God’s incredible engineering. The perfect food, all in one tidy little package. Here’s to the chicken and the egg!
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What a delight! I loved this post, and God’s glory in creation all over it. Thanks for sharing, Angie. Wish I could drop by and see your hens, and you with them. 🙂
Any time you’re in the area, drop on by for a giggle and a cackle! :-). Chickens are fascinating–and make me appreciate God’s genius. 🙂
thank you for sharing this wonderful information. growing up on a farm with lots of chickens I knew a lot of this, just not in particular words. we had an old lady who helped mom and some of us kids understand how and why things worked with chickens. she was a cool lady. she used the analogy of “down the river and around the bends” around each b3end in the river is when different things with the egg happened.
I love that analogy! Much better than an “assembly line,” since lines are straight and the oviduct is more curved like a river. :-0. What a blessed childhood you had!
So interesting! Thanks for sharing!!
You’re very welcome–thanks for listening to my ode to an egg. 🙂
Oh my. That egg within the egg “cracked” me up!
You should have seen my face when I cracked it! Not what I was egg-pecting!
Amazing! That old commercial jingle, the amazing edible egg…Not sure if they meant us to marvel at God’s creativity and intricate details, but wow, you are sharing some awesome stuff!
Nope, I think it was the incredible edible egg! (mixing up my jingles)
I remember that jingle–I can still sing it! 🙂
Very interesting, I kinda have a weak stomach so all the information made me a little queasy but I will get over it as I love scrambled eggs! It is a wonder to know we serve a Great and Wonderful God who didn’t overlook one detail in His creation!
I have a friend who wouldn’t eat eggs because she was terrified at the thought of eating a baby chick. I assured her that wouldn’t happen . . . at least, not unless she took an egg from under a sitting hen. That would traumatize anyone!
Marvelous engineering indeed! I found this information SO INTRIGUING! Thanks for sharing it with us.
Glad you enjoyed it. 🙂
This is fascinating! My daughters hatched quails for a 4H project. We had three hens laying last summer. Down to two that should start laying again in a couple of weeks. I think everything you shared applies to them as well. They are amazing little creatures, and we get a kick out of gathering their little eggs all summer. Granted, we need more than 60 to feed our family Sunday breakfast, but it’s a treat!
Sixty quail eggs . . . that’s a lot of eggs. :-). And all from three hens? They were busy!
This was fascinating. My sister raises chickens and my niece shows them with 4H but I’ve NEVER heard this awesome explanation. Thanks.
I didn’t know a thing about it until I started raising chickens. Then I started learning and now I can’t stop. 🙂
Wow, Angie, I had NO idea about how eggs develop. Sooooo interesting. Thank you!!
Thank YOU, Roxy! :-). Isn’t God amazing to think of such a creature?
This is SO fascinating! I had no idea about egg production, and you explained it so well – – thank you! I’m sure your chickens must love you, because you sure seem to adore them – – so sweet. 🙂
Thanks for sharing this eggs-cellent post! 😉
You’re welcome. I don’t know if my girls adore me, but they come running when they hear my voice–probably because they’re hoping for treats! 🙂
I really enjoy your chicken posts and feel like I gained egg-straordinary amounts of interesting information, Angela! The creativity, innovation, and majesty of our God blows my mind! Thank you for sharing this egg-cellent post! 🐔🐣
You’re very welcome! 🙂
Fascinating! Thank you for sharing.
🙂
What an eggs-cellent lesson on chickens egg production facilities! Thank you for teaching us about chickens. God’s imagination and creations are fascinating.
I ordered your boom, “The Chicken Who Loved Books”, and my 4 year old granddaughter loves it! We have read it several times each day while she has been visiting me. She laughs at Little Red’s antics and has been running around shouting “Book-book-kaka-book!”
Sorry about the typos!
They were cute typos. :-). And I am so happy your granddaughter loves “The Chicken Who Loved Books.” Hysterical that she clucks that line! She must have had a very enthusiastic reader! 🙂
❤️
Amazing, stunning. What a detailed description of our Father’s design for these oh so important creatures from whom we greatly benefit. Mahalo (thx) many times Ms Hunt. I hope my setup to print this to share, happens! I’m an 85 year old grandma. During my childhood, my family had a hen house with all the ‘furnishings’. My mom was the care taker of these very important additions to our family needs.
Thank you also for your books. Several line the shelves of my kindle library. God bless you as you continue to serve Him!!!